Why is the weather forecast date wrong?

Usually, the weather forecast is based on the thickness distribution and movement trend of clouds in the earth's atmosphere photographed by satellites to predict the future weather conditions in various areas on the ground. There may be many uncertain variables, such as the change of high and low pressure and the change of cloud movement direction, so it is normal that the time is not so accurate, and it cannot be called a mistake. After all, what we can do is to predict, not to control current events. . .